1. Field of the Invention
The present invention relates to a system and method for deployment of seismic sensors and in particular to the deployment and retrieval of self-propelled, autonomous seismic sensors in an ocean environment.
2. Description of the Related Art
Historically, ocean bottom seismic data acquisition sensor packaging and deployment has taken the form of either self-contained instruments dropped in the water or sensor cables streamed behind a surface support ship. Typically, self-contained seismic instruments are dropped off the back of a surface support ship where they descend under the influence of their own negative buoyancy to drift down through a water column until they contact the sea-floor. This drop and drift system is imprecise and potentially leaves seismic survey areas uncovered. Typically, the seismic instruments have been deployed from the back of a surface support ship or vessel. Alternatively, surface towing vessels have been used for surface support and deployment of ocean bottom cables (OBC) which are dragged or draped over a seabed. In other instances, seismic cables and instruments have been deployed with the aid of remotely controlled vehicles. This remotely controlled procedure is limited by the operational speed and capacity of remotely operated deployment vehicles. Moreover, conventional ship borne seismic cable deployment systems are limited in the number of cables that they feasibly can deploy and accurately control during seismic operations. At a certain point, the number of cables in the water becomes unwieldly. Thus, there is a need for a system that avoids the problems of the prior art.